1. Field of the Invention
The present invention relates to pharmaceutical compounds useful for the increase of immune function and the prevention of infectious disease. The pharmaceutical composition is very safe.
2. Description of the Prior Art
U.S. Pat. No. 4,442,087 disclosed an interferon inducer isolated from tissue of a plant of the genus artemisia. U.S. Pat. No. 4,419,349 disclosed that the interferon inducer is believed to be a homogeneous polymer of protein and sugars containing phosphoric acid. U.S. Pat. No. 4,145,415 disclosed that three new active substances have therapeutic activity in mammals for improving or curing hepatic diseases, antitumor activity upon oral administration or antiinflammatory activity. U.S. Pat. No. 4,431,639 disclosed that an adjuvant is effective for stimulating the production of lymphocytes in the circulating blood of a mammal and the adjuvant is an extract from atractylis lyrata S. Meanwhile, The Journal of Tradition Chinese Medicine disclosed that the plant of Astragalus membranaceus has been used as a natural medicine for successfully treating common cold or acute upper respiratory tract infection in human. [The Journal of Tradition Chinese Medicine 21 (1): 71-76, 1980.]